I. Field of the Invention
The invention generally relates to a method of manufacturing flock transfers. Specifically, the invention is directed to multicolor flock transfers which exhibit an enhanced texture.
II. Description of the Prior Art
There are two basic methods of applying a multicolor flock design to a surface. The first method is referred to an a multicolor direct flocking. The flock is applied directly to the surface that forms the finished product. Usually wallpaper, carpets and decorative elements of garments are produced in this manner.
An example of direct flocking is found in U.S. Pat. No. 3,793,050, to Mumpower. This particular direct flocking method is unique in that it allows the use of different color and size of flock in the same design surface to be flocked. The adhesive is rendered tacky and each color of flock is passed through a screen that restricts that color to the desired part of the adhesive layer. A multicolor flock design is thus obtained on the surface.
Multicolor direct flocking suffers a number of disadvantages. It is an exacting procedure with many variables to be controlled requiring specialized flocking equipment and an environment that is controlled for relative humidity. During the startup of such a procedure many reject-quality articles may result as the variables are adjusted by trial and error, and the desired result is found. The procedure is relatively slow since usually only one article at a time may be decorated. Further, if the article to be decorated has an uneven surface like many textiles, then density of the flock, control, speed and the quality of the finished design i.e., sharpness of lines separating colors, vivid images, etc., would be adversely affected. Thus, direct flocking has been limited in use in the world.
Flock transfers are a second method of employing flock fibers in a decorative manner. Examples of these transfers are illustrated in U.S. Pat. Nos. 4,292,100 and 4,396,662, both to Higashiguchi and UK Patent applications No. 2,065,031 to Maitland, and No. 2,126,951 to Transworth. Transfers are formed by applying flock to a release sheet having a temporary release adhesive coating. The flock is then dyed with different color inks and coated with a binding layer and hot melt adhesive in a desired decorative design. The transfers are applied to articles with heat and pressure. The release sheet is peeled away leaving a finished decorative design.
Conventional multicolor flock transfers have not achieved significant commercial success in the United States due to a number of inherent limitations. The basic underlying problem is that a richly textured appearance has not been achieved using flock to justify the additional cost for conventional screen printing. The flock transfers are relatively flat and thus a plush textured multicolored look is not achieved. From experience, original flock transfers are far less permanent in their application, and mainly consist of rayon fibers colored with pigment inks, versus the new style of fibers that may be more wash-and color-fast yarn-dyed or spun-dyed nylon or polyester type of fibers. Also, unlike original flock transfers, this current invention has colors which are far more brilliant which is a function of the light being transmitted through the more translucent plastic (nylon or polyester) and longer fibers, reflected off of the backing adhesive and transmitted back though the fibers resulting in a much more intense color for observance when the transfers are applied and viewed by any nearby observer.
A fundamental limitation of the flock transfer manufacturing method is the problem of penetrating the flock fiber with printing ink to form the desired design. Typical flocks used in flock transfers are only 0.3 mm long. This is unlike direct flocking which can use colored flocks of approximately 1 mm to 3 mm in length.
An objective of the present invention is to produce a plush textured flock transfer which presents a plush textured three dimensional appearance. A second objective is to provide a means of producing plush-textured multicolored flock transfers which can be manufactured in batches containing more than one transfer per batch. This invention also includes a specially-pattern to release adhesive pattern that has bleed-off lines which carry the high voltage current used for the electrostatic fiber coating, to the ground, and therefore, helps to enhance the counter potential effect or power of the electrostatic field applied during the flocking process. A third objective of the invention is to provide a method of decorating articles with a multicolor plush textured design which overcomes the disadvantages and limitations of direct flocking. Finally, an objective of the invention is to allow manufacturers of products to economically make use of plushly-textured flock designs in place of screen printed designs. In one embodiment for this invention, the fibers arranged in proximity with the outside edges of the transfer feature a diminishing density to prevent impression lines in the substrate material to which the transfer is being applied; and that insert materials can be incorporated into the transfer for a mixed-media effect, as distinct from the current type of plush transfers available upon the market.